A croissant is a buttery, flaky, viennoiserie pastry of Austrian and French origin, named for its historical crescent shape. Croissants and other viennoiserie are made of layered yeast-leavened dough. The dough is layered with butter, rolled and folded several times in succession, then rolled into a sheet, in a technique called laminating. The process results in a layered, flaky texture, similar to a puff pastry.
Crescent-shaped bread has been made since the Renaissance and crescent-shaped cakes possibly since antiquity. Croissants have long been a staple of Austrian and French bakeries and pâtisseries. In the late 1970s, the development of factory-made, frozen, pre-formed but unbaked dough made them into a fast food which can be freshly baked by unskilled labor. The croissant bakery, notably the La Croissanterie chain, was explicitly a French response to American-style fast food, and as of 2008 30–40% of the croissants sold in French bakeries and patisseries were baked from frozen dough.
Croissants are a common part of a continental breakfast in France.
The kipferl, the origin of croissant can be dated back to at least the 13th century in Austria and came in various shapes. The kipferl can be made plain or with nuts or other fillings (some consider the rugelach a form of kipferl). Some Egyptians claim, arguably, that the kipferl may have been based on the feeder meshaltet pastry known to the Egyptians.
The birth of the croissant itself—that is, its adaptation from the plainer form of kipferl, before the invention of viennoiseries—can be dated to at least 1839 (some say 1838) when an Austrian artillery officer, August Zang, founded a Viennese bakery ("Boulangerie Viennoise") at 92, rue de Richelieu in Paris. This bakery, which served Viennese specialties including the kipferl and the Vienna loaf, quickly became popular and inspired French imitators (and the concept, if not the term, of viennoiserie, a 20th-century term for supposedly Vienna-style pastries).
The French version of the kipferl was named for its crescent (croissant) shape and has become an identifiable shape across the world.